Two to three no. a year; Spring 2000-; Title from PDF title screen (viewed May 1, 2006).; Latest issue consulted: Spring 2006 (May 1, 2006).; Chronological designation flips from season to month and back to season.
Title from cover (viewed on Apr. 21, 2011).; "7/10"--Colophon.; Funding for the printing of this publication was provided by the US EPA through a section 319(h) grant administered by the NC Division of Water Quality.